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1// SPDX-License-Identifier: GPL-2.0-only
2/**
3 * IIO driver for the MiraMEMS DA280 3-axis accelerometer and
4 * IIO driver for the MiraMEMS DA226 2-axis accelerometer
5 *
6 * Copyright (c) 2016 Hans de Goede <hdegoede@redhat.com>
7 */
8
9#include <linux/module.h>
10#include <linux/i2c.h>
11#include <linux/acpi.h>
12#include <linux/iio/iio.h>
13#include <linux/iio/sysfs.h>
14#include <linux/byteorder/generic.h>
15
16#define DA280_REG_CHIP_ID 0x01
17#define DA280_REG_ACC_X_LSB 0x02
18#define DA280_REG_ACC_Y_LSB 0x04
19#define DA280_REG_ACC_Z_LSB 0x06
20#define DA280_REG_MODE_BW 0x11
21
22#define DA280_CHIP_ID 0x13
23#define DA280_MODE_ENABLE 0x1e
24#define DA280_MODE_DISABLE 0x9e
25
26enum da280_chipset { da226, da280 };
27
28/*
29 * a value of + or -4096 corresponds to + or - 1G
30 * scale = 9.81 / 4096 = 0.002395019
31 */
32
33static const int da280_nscale = 2395019;
34
35#define DA280_CHANNEL(reg, axis) { \
36 .type = IIO_ACCEL, \
37 .address = reg, \
38 .modified = 1, \
39 .channel2 = IIO_MOD_##axis, \
40 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
41 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
42}
43
44static const struct iio_chan_spec da280_channels[] = {
45 DA280_CHANNEL(DA280_REG_ACC_X_LSB, X),
46 DA280_CHANNEL(DA280_REG_ACC_Y_LSB, Y),
47 DA280_CHANNEL(DA280_REG_ACC_Z_LSB, Z),
48};
49
50struct da280_data {
51 struct i2c_client *client;
52};
53
54static int da280_enable(struct i2c_client *client, bool enable)
55{
56 u8 data = enable ? DA280_MODE_ENABLE : DA280_MODE_DISABLE;
57
58 return i2c_smbus_write_byte_data(client, DA280_REG_MODE_BW, data);
59}
60
61static int da280_read_raw(struct iio_dev *indio_dev,
62 struct iio_chan_spec const *chan,
63 int *val, int *val2, long mask)
64{
65 struct da280_data *data = iio_priv(indio_dev);
66 int ret;
67
68 switch (mask) {
69 case IIO_CHAN_INFO_RAW:
70 ret = i2c_smbus_read_word_data(data->client, chan->address);
71 if (ret < 0)
72 return ret;
73 /*
74 * Values are 14 bits, stored as 16 bits with the 2
75 * least significant bits always 0.
76 */
77 *val = (short)ret >> 2;
78 return IIO_VAL_INT;
79 case IIO_CHAN_INFO_SCALE:
80 *val = 0;
81 *val2 = da280_nscale;
82 return IIO_VAL_INT_PLUS_NANO;
83 default:
84 return -EINVAL;
85 }
86}
87
88static const struct iio_info da280_info = {
89 .read_raw = da280_read_raw,
90};
91
92static enum da280_chipset da280_match_acpi_device(struct device *dev)
93{
94 const struct acpi_device_id *id;
95
96 id = acpi_match_device(dev->driver->acpi_match_table, dev);
97 if (!id)
98 return -EINVAL;
99
100 return (enum da280_chipset) id->driver_data;
101}
102
103static int da280_probe(struct i2c_client *client,
104 const struct i2c_device_id *id)
105{
106 int ret;
107 struct iio_dev *indio_dev;
108 struct da280_data *data;
109 enum da280_chipset chip;
110
111 ret = i2c_smbus_read_byte_data(client, DA280_REG_CHIP_ID);
112 if (ret != DA280_CHIP_ID)
113 return (ret < 0) ? ret : -ENODEV;
114
115 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
116 if (!indio_dev)
117 return -ENOMEM;
118
119 data = iio_priv(indio_dev);
120 data->client = client;
121 i2c_set_clientdata(client, indio_dev);
122
123 indio_dev->dev.parent = &client->dev;
124 indio_dev->info = &da280_info;
125 indio_dev->modes = INDIO_DIRECT_MODE;
126 indio_dev->channels = da280_channels;
127
128 if (ACPI_HANDLE(&client->dev)) {
129 chip = da280_match_acpi_device(&client->dev);
130 } else {
131 chip = id->driver_data;
132 }
133
134 if (chip == da226) {
135 indio_dev->name = "da226";
136 indio_dev->num_channels = 2;
137 } else {
138 indio_dev->name = "da280";
139 indio_dev->num_channels = 3;
140 }
141
142 ret = da280_enable(client, true);
143 if (ret < 0)
144 return ret;
145
146 ret = iio_device_register(indio_dev);
147 if (ret < 0) {
148 dev_err(&client->dev, "device_register failed\n");
149 da280_enable(client, false);
150 }
151
152 return ret;
153}
154
155static int da280_remove(struct i2c_client *client)
156{
157 struct iio_dev *indio_dev = i2c_get_clientdata(client);
158
159 iio_device_unregister(indio_dev);
160
161 return da280_enable(client, false);
162}
163
164#ifdef CONFIG_PM_SLEEP
165static int da280_suspend(struct device *dev)
166{
167 return da280_enable(to_i2c_client(dev), false);
168}
169
170static int da280_resume(struct device *dev)
171{
172 return da280_enable(to_i2c_client(dev), true);
173}
174#endif
175
176static SIMPLE_DEV_PM_OPS(da280_pm_ops, da280_suspend, da280_resume);
177
178static const struct acpi_device_id da280_acpi_match[] = {
179 {"MIRAACC", da280},
180 {},
181};
182MODULE_DEVICE_TABLE(acpi, da280_acpi_match);
183
184static const struct i2c_device_id da280_i2c_id[] = {
185 { "da226", da226 },
186 { "da280", da280 },
187 {}
188};
189MODULE_DEVICE_TABLE(i2c, da280_i2c_id);
190
191static struct i2c_driver da280_driver = {
192 .driver = {
193 .name = "da280",
194 .acpi_match_table = ACPI_PTR(da280_acpi_match),
195 .pm = &da280_pm_ops,
196 },
197 .probe = da280_probe,
198 .remove = da280_remove,
199 .id_table = da280_i2c_id,
200};
201
202module_i2c_driver(da280_driver);
203
204MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
205MODULE_DESCRIPTION("MiraMEMS DA280 3-Axis Accelerometer driver");
206MODULE_LICENSE("GPL v2");